Oswald did it, and he did it alone.

This video presents a good summary of the facts (as opposed to conjecture and mythology) surrounding one of the most tragic events in American history. Polls continue to show that most people believe there was some kind of elaborate conspiracy at the heart of Kennedy's murder. The only problem is that there is not a shred of credible evidence that supports that. Belief in a conspiracy can only be sustained by ignoring the mountains of actual hard evidence, all of which points to Oswald.

Two books do an excellent job debunking the myths, misinformation, and outright lies that are pervasive among conspiracy theorists. There are others, but IMO these are the best.

Case Closed by Gerald Posner

Reclaiming History by Vincent Bugliosi (This book is massive and took me more than six months to read. It is available in almost any well stocked public library.)